A variable torque generator has been described in priority U.S. Pat. Nos. 8,338,481; 8,485,933; and 8,702,552 as well as priority PCT/US2010/042519 published as WO2011/011358. The variable torque generator has one of an axially moveable rotor and stator with respect to its stationary or moveable counterpart stator or rotor so as to vary the amount of overlap by the stator with respect to the rotor from a minimum when the stator is displaced from the rotor to a maximum value when the stator and rotor are proximate to or overlap one another.
In particular, there is described in, for example, WO2011/011358 or U.S. Pat. No. 8,338,481 (the U.S., '481 patent), the concept of measuring torque/rpm on an output shaft of a system such as a wind or river/tidal/ocean wave/ocean current turbine (which may be referred to herein as a marine hydrokinetic (MHK) turbine) for providing a constant output from a variable flow input. The measured torque/rpm value may be compared with a torque/rpm value stored in a memory and, if the measured torque/rpm is high in comparison, then, the moveable rotor or stator of a variable torque generator may be moved axially to a position more in keeping with the high measured torque/rpm value, i.e. such that the stator is moved away from the rotor axially under motor control through a feedback loop. When the measured torque/rpm is low in comparison with an expected value, the moveable rotor or stator may be moved axially toward one another to match a low value of torque/rpm so that the speed of the output shaft may increase and vice versa. This variable torque generator process continues so as to maintain a relationship between speed of input (such as wind or river/tide/ocean wave/ocean current) to match a desired rotational speed of output shaft and to maintain output shaft speed, for example, if used as an electric power generator, to produce 60 Hz U.S. electric frequency or in Europe 50 Hz European frequency electric power.
In either the '481 U.S. patent or the WO 2011/011358 printed publication priority documents, FIG. 8 shows the concept of an infinitely variable torque generator, meaning that the one of the moveable rotor or the stator may be moved, for example, by a servo motor, not shown, to any position of proximity to or distance from one another or such that their respective magnetic flux fields are located far away from one another so as to not couple with one another or to couple with one another, for example, to have an effect to cause a coupling of rotor and stator and a magnetic force field tending to cause the rotor to be stationary with the stator or move with the stator. In FIG. 10, the rotor and stator of the variable torque generator are shown such that the rotor 810 is directly coupled to the shaft 820. “When the stator parts 830(a) and 830(b) are moved away from rotor 810, a minimum input torque results. The operation of a control may be as follows via measuring a torque value stored in memory proximate to the maximum torque that a given rotor shaft 820 may receive (a maximum allowable torque value), the stator parts 830(a) and 830(b) may be moved by a motor (not shown) to be in removed torque position or a position in between maximum and minimum torque positions whereby a close-to-maximum torque position may be achieved in relation to the measured torque and the maximum allowable torque(/rpm) value or value stored in memory.”
There remains a need in the art to provide applications of such a variable torque/power generator assembly in connection with the generation of electrical energy/power (VPG) from renewable sources such as wind and river/tide/ocean wave/ocean current among other possible applications such as in vehicle engines.